This application claims the benefit of European Patent Application Serial Number 00 103 183.0 entitled xe2x80x9cMisch- und Applikationskapsel, filed on Feb. 17, 2000.
The present invention generally relates to a mixing and application capsule for the production and application of expellable materials, in particular for the production of ready-for-use dental preparations and for application of the preparation directly to the location to be treated.
Mixing and application containers are known from German patent Nos. 23 24 296 and 35 66 497.
German patent No. 23 24 296 describes a mixing container having a laterally mounted foil pad and a straight dispensing cannula. The dispensing cannula is closed by a pin which can be withdrawn outwardly. In the case of containers in which the dispensing nozzle is closed by a pin until the time of the dispensing procedure, the problem which arises is that for the dispensing procedure to be implemented the nozzle should admittedly be conical over its length and funnel-shaped in the entry region, but that can give rise to the existence of dead spaces in relation to the pin and the wall of the nozzle. Components can solidify in such spaces during storage or transportation and then do not take part in the mixing procedure. In addition, in the application operation that unmixed component is the first to issue and it prevents or influences proper hardening. Furthermore the pin can be easily removed from the dispensing nozzle, which can result in the content of the capsule being adversely affected. Furthermore waste unavoidably occurs when the closure plug is taken out.
German patent No. 35 66 497 seeks to remedy that disadvantage by virtue of pivotability of the dispensing nozzle. A disadvantage of that design configuration however is the cannula dimensioning which is restricted by virtue of the pivotability involved. As, in the closed condition, the cannula projects beyond the lateral dimensions of the capsule body, the capsule holder of the mixing apparatuses as are described for example in European patent No. 29 17 33 must be provided with recesses or openings in order to permit the capsule to be securely held. A further disadvantage of the limited cannula dimensioning is found in practical use. If the user interrupts the application, the material is frequently observed to continue to come out of the cannula, although no pressure whatsoever is being applied to the application piston.
German patent application No. 15 86 866 describes containers having a plurality of mutually separated chambers, wherein inner and outer discs provided with openings are arranged rotatably. For sealing purposes, those discs are of curved shapes in order to press against each other after assembly.
The known and described apparatuses admittedly endeavour to make the application of a substance which is capable of flow and the admixing thereof more convenient, but they result in complex, expensive and difficult processes and they give rise to special demands in terms of the mixing and application apparatuses. In addition capsule production is also a complex and problematical matter.
Briefly described, the present invention provides a capsule for mixing and applying dental cement. The capsule includes a capsule body having a cylindrical shape, a longitudinal axis and a dispensing end. A mixing chamber is located in the capsule body, and it is designed and arranged to hold dental cement. The mixing chamber has an opening region. A piston is located in the capsule body and in the mixing chamber to be axially displaceable for expelling mixed dental cement through the opening region. An exit opening is located at the dispensing end of the capsule body and in the opening region. A closure cap is designed and arranged to cover the opening region. A clamping device is designed and arranged to rotatably connect the closure cap to the capsule body in the opening region to be in opposite fluid-sealing relationship. An unbent application cannula is fixedly mounted to the closure cap at an angle of approximately 10xc2x0 to 80xc2x0 with respect to the longitudinal axis of the capsule body.
Furthermore, the present invention provides a capsule for mixing at least two components and for applying a ready-for-use dental cement. The components react with each other for the production of the ready-for-use dental cement and for the application of the dental cement directly onto a location to be treated. The capsule includes a capsule body having a cylindrical shape, a longitudinal axis, a dispensing end and an opening. A mixing chamber is located in the capsule body, and it is designed and arranged to hold a first component. The mixing chamber has an opening region. A foil pad is designed and arranged to hold a second component and to close the opening. A clasp portion is designed and arranged to connect the foil pad to the capsule body. A piston is located at a rear end of the capsule body and in the capsule body and in the mixing chamber to be axially displaceable for expelling mixed dental cement through the opening region. An exit opening is located at the dispensing end of the capsule body and in the opening region. A closure cap is designed and arranged to cover the opening region. A clamping device is designed and arranged to rotatably connect the closure cap to the capsule body in the opening region to be in opposite fluid-sealing relationship. An unbent application cannula having an internal contour and an inlet region is fixedly mounted to the closure cap at an angle of approximately 10xc2x0 to 80xc2x0 with respect to the longitudinal axis. The application cannula is arranged on the closure cap such that the exit opening and the inlet region of the application cannula can be positioned in mutually superposed relationship and such that the exit opening and the internal contour of the application cannula are of the same dimensions in the inlet region of the application cannula.
The novel capsule is in practice operationally reliable and user-friendly and avoids the disadvantages which are known from the state of the art. Surprisingly the mixing and application capsule according to the invention provides for simple production without problems, for example by means of a plastic injection moulding technology, an uncomplicated configuration, and also safe storage and reliable use, from the point of view of the user. In particular the combination of the essential features of the capsule, as are set forth in the characterising portions of the claims, afford a mixing and application capsule which enjoys the following advantages:
simple activation for admixing two or more components by lateral pressure applied to the clasp or bar portion;
mixing is possible in current mixing apparatuses;
an interruption in the application procedure can be effected without much fuss, the material does not continue to run;
no capsule components project beyond the dimensions of the capsule body, unintended damage to capsule components or the capsule is thereby avoided;
the opened and closed conditions of the capsule can be clearly perceived and can be set by simple rotational movement;
fluid-sealing closure devices provide for secure and reliable storage and actuating conditions and contamination of the components of the mixture is avoided;
the mutually matched dimensioning of the outlet openings permits materials of varying viscosities to be applied without problem;
the producers and suppliers of dental preparations to be mixed require only one basic capsule design for materials of varying viscosities;
application with current apparatuses is possible; and
application of the finished mixed preparation directly to the location to be treated, for example into a dental cavity, is possible without any fuss.
The subject-matter of the invention is a capsule for receiving, mixing and application of substances which are capable of flow, that is to say which can be squeezed out. This involves a capsule in which two or more components are mixed in the capsule, the components forming the substance which is capable of flow, and can thereafter be applied directly to the location to be treated.
The novel mixing and application capsule does not suffer from the stated disadvantages known from the prior art. The capsule is easy to operate from the point of view of the user and, in the admixing and application operation, it affords a high level of security, reliability and accuracy. The novel capsule is compact and easy to produce.
Other features and advantages of the present invention will become apparent to one with skill in the art upon examination of the following drawings and the detailed description. It is intended that all such additional features and advantages be included herein within the scope of the present invention, as defined by the claims.